1. Field:
The field of the invention is ratchet-type wrenches and more particularly those of the open end or broken circle design.
2. Prior Art:
None of the previous embodiments of open ended ratchet wrenches have fully exploited the potential of such wrenches. These prior designs are commonly so bulky as to seriously impair their usefulness in restricted work areas. Some are less bulky, but suffer from impaired strength, limiting their usefulness for heavy wrenching and shortening their useful life. The handle operated, spring loaded jaw of U.S. Pat. No. 2,757,564, substantially increases the working space required, and the entire wrenching force must be resisted by a small jaw pivot pin. Similarly, the jaw mounted ratchet pawls in U.S. Pat. No. 2,401,128 substantially increase the size of the jaws of the wrench. U.S. Pat. No. 2,376,575, discloses similar jaw mounted pawls undesirably increasing the necessary width of the wrench. The insertion and retention of the wrenching discs in the prior designs involve complicated components, such as the spring clip of U.S. Pat. No. 2,401,128 and the sliding arcuate key of U.S. Pat. No. 2,376,575. Both of these designs require removal of the wrenching insert laterally of the wrench, increasing required lateral space for use of the wrench. U.S. Pat. No. 1,081,117 has two rotating jaws, used only to laterally retain the wrenching disc, thus providing no strength but nevertheless increasing the size of the wrench. Ratchet teeth on the disc circumference are engaged by a pivoting pawl in the strength bearing portion of the wrench. Because of the rotating retaining jaws, the strength bearing portion of the wrench head is necessarily thinner or the wrench unnecessarily thick. The permissible wrenching force is limited since it must be resisted by the small pawl pivot pins.